Sheet lath



J. H. DEAN 1,726,696

SHEET LATE Sept. 3, 1929.

Filed Jan. 11, 1928 Patented Sept. 3, 1929.

UhlTED STATES JAMES H, DEAN, OF LUDINGTON, MICHIGAN.

SHEET LATH.

Application filed. January 11, 1928. Serial No. 245,833.

This invention relates to improvements in sheet lath and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

The primary object of the invention 1s to provide a lath of this kind which is so constructed as to make it practical to employ a lighter gauge sheet metal and one which includes longitudinally extending ribs and transversely extending plaster retarding members so formed as to not only impart structural stiffness to the lath but also to permit the formation of the plaster keys with but a minimum amount of plaster.

Another object of the invention is to proide a lath of this kind wherein the sheet is formed to provide longitudinally extending parallel spaced ribs on the rear side thereof with a row of transversely extending plaster retarding members between adjacent ribs, each of which members includes at least two retarding seats that terminate at the corners or shoulders of said ribs, with one seat offset from the other but connected thereto by a web which decreases in depth toward its ends.

These objects of the invention as well as others together with the many advantages thereof will more fully appear as I proceed with my specification.

In the drawing Fig. v1 is a perspective view of a corner fragment of sheet lath embodying the preferred form of my invention.

Fig. 2 is a view in elevation of said corner fragment of sheet lath as viewed from the frontor plaster receiving side or face thereof.

Fig. 3 represents a transverse vertical section through one lateral margin of the lath as taken on the line 33 of Fig. 2.

Fig. 4: represents a longitudinal section th-erethrough as taken on the line H of Fig. 2.

Fig. 5 is a fragmentary view similar to Fig. i but on an enlarged scale and shows the manner in which the plaster keys are formed in the application of plaster to the lath.

In general, my improved lath is made from a single thin metallic sheet by providing on one side thereof, longitudinally extending ribs that not only stiffen the sheet in that direction, but provide the necessary means determining the effective spacing of the plaster retarding members from the associated building wall elements, which members extend transversely between the ribs and are so formed as to not only form the plaster key from a minimum amount of plaster but to stiffen the sheet in that direction.

Referring now in detail to that embodiment of the invention illustrated in the accompanying drawing, 1 indicates as a whole the body of a thin metallic sheet from which my improved lath is made. Formed from the sheet body itself by any suitable means and upon what is hereinafter termed the rear side thereof is a plurality of spaced ribs 2 which extend parallel with each other and with the longitudinal edges of the sheet, with one of said ribs at each edge thereof, said ribs joining with the remaining portions of the sheet by rounded corners or shoulders 38. Preferably these ribs which determine the spacing of the front face of the finished lath from the associated building wall elements to which they are attached, are V shaped not only because they better resist collapse but also because the ribs of one sheet will nest in those of adjacent sheets when stacked in bundle form for shipment, and also because they permit a better connection between the longitudinal margins of adjacent sheets on said building wall elements, as is most apparent.

Between adjacent ribs and formed from the body of the sheets, are rows of longitudinally spaced, transversely extending plaster retarding members each indicated as a whole by the numeral 4. Each retarding member which extends from corner to corner 33 between adjacent ribs comprises a front and preferably flat plaster retarding seat 5 and a rear plaster retarding seat 6, the latter being depressed into a transverse curvature with respect to the first mentioned seat, but connected thereto by a web 7 that decreases in depth from its mid-portion towards its ends as is best shown in Fig. 3. Preferably but not necessarily so, said web is disposed at less than ,a right angle to the planes of said seats as best shown in Fig. 5 and its greatest depth is less than the depth of the ribs so that when the finished sheet lath is applied to a smooth flat wall, the plaster can pass through the openings between adjacent retarding members to key behind the rearmost seat. 1

In arranging the retarding members in one row with respect to those in the next row, I face those in one row in a direction opposite those in the adjacent rows and I relatively offset them as best shown in Fig. 2 wherein it will be noticed that the front seats of the retarding members in one row are disposed in the planes of the rear seats of the retarding members in the adjacent rows. In this manner the finished lath is not only materially stiffened but the plaster applied to the lath is better secured thereto by the staggered arrangement of the keys. I

In Fig. 5 I have shown only ascratch coat 8 of plaster applied to the lath and it will be apparent that in applying the plaster, portions thereof are guided or deflected by the inclined Webs 7 to How over the rear seat and through the openings between the re tarding members to provide the keys 9 that insure the proper adhesion or securement of the plaster to the lath without the excessive waste in forming keys larger than necessary. In this manner the lath is really a plaster saver.

It is apparent from the foregoing description that the said seats of each retarding member extend from one associated rib corner 3 to the other and thus makes each member as long as possible and permits the curved formation of the rear seats without checking at their ends where they merge into said corners. Again the retarding members in effect provide innumerable transversely extending 2 bar like trusses in the lath whereby it is rigidified and stiffened in that direction. My improved lath is of especial advantage where tile is applied to the plastic material disposed upon the lath, because the retarding members, resist the too rapid flow of said material through the openings be tween said members, under the action of the tapping the tile receives in placing it upon said material.

vVhile in describing the invention I have referred in great detail to the form arrangement and construction of the various parts thereof, the same is to be considered as illustrative only so that I do not wish to be limited thereto except as may be pointed out in the appended claims.

I claim as my invention:

1. A sheet lath embodying therein a thin metallic sheet provided with longitudinally extending ribs spaced apart on one side there of, portions of the sheet between the ribs being formed with depressions extending substantially at right angles with the ribs thus providing offset plaster retarding surfaces one offset being approximately in the plane of the vertex of the rib and the other offset substantially in the plane of the base of a rib and a Web portion on one side of each depression connecting the two plaster retarding surfaces.

2. A sheet lath embodying therein a thin metallic sheet provided with longitudinally extending ribs spaced apart on one side thereof, portions of the sheet between the ribs being formed with rows of depressions the de pressions in adjacent rows being offset relatively to each other each depression extending substantially at right angles to the ribs thus providing two offset plaster retarding surfaces, one offset being approximately in the plane of the vertex of the rib and the other offset being substantially in the plane of the base of a rib and a Web portion on one side of said depressions connecting the two plaster retarding surfaces.

8. A. sheet lath embodying therein a thin metallic sheet provided with longitudinally extending ribs spaced apart on one side thereof, port-ions of the sheetbetween the ribs being formed with depressions, each depression extending substantially at right angles to the ribs thus providing two offset plaster retard ing surfaces, in diflerent planes on opposite sides of the sheet and a web portion on one side only of each depression which decreases in depth from its mid portion towards its ends and connects the two plaster retarding surfaces.

4. A sheet lath embodying therein a thin metallic sheet provided with longitudinally extending ribs spaced apart on one side thereof, portions of the sheet between the ribs being formed with depressions, each depression being open on one side and into which plaster may be keyed, said depressions extending substantially at rightangles to the ribs thus providing two offset plaster retarding surfaces, one offset being below the general surface of the sheet and the other offset being in substantially the general plane of the sheet, and a web portion inclined to said surface on one side of said depression said inclined web surface connecting the two plaster retarding surfaces.

In testimony whereof, I have hereunto set my hand, this third day of January, 1928.

JAMES H. D AN. 

